upstream/opnsense-src
1
0
Fork 0
mirror of https://github.com/opnsense/src.git synced 2026-05-28 04:12:45 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions

timerfd: Fix interval callout scheduling

Browse source 
When a timerfd interval callout misses its scheduled activation time, a
differential is calculated based on the actual activation time and the
scheduled activation time. This differential is divided by the timerfd's
interval time and the quotient is added to the timerfd's counter.

Before this change, the next callout was scheduled to activate at:
scheduled activation time + timerfd interval.

This change fixes the scheduling of the next callout to activate at:
actual activation time + timerfd interval - remainder.

Security:		FreeBSD-26:06.timerfd
Approved by:		so
Reviewed by:		markj
Differential Revision:	https://reviews.freebsd.org/D55790
MFC after:		2 weeks

(cherry picked from commit 85c0f1a87da1fd1eb3e646e86f70e630c48da91a)
(cherry picked from commit 3c00f603a2801fd780666f9e94a26f264a887c90)
This commit is contained in:
Jake Freeland 2026-03-20 01:33:03 -05:00 committed by Franco Fichtner
parent 74e09b2d0d
commit 6ffe3a31b8
1 changed files with 13 additions and 11 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

24
sys/kern/sys_timerfd.c
View file

@ -394,23 +394,25 @@ static void
timerfd_expire(void *arg)
{
struct timerfd *tfd = (struct timerfd *)arg;
struct timespec uptime;
sbintime_t exp, interval, now, next, diff;
++tfd->tfd_count;
tfd->tfd_expired = true;
if (timespecisset(&tfd->tfd_time.it_interval)) {
exp = tstosbt(tfd->tfd_time.it_value);
interval = tstosbt(tfd->tfd_time.it_interval);
now = sbinuptime();
next = now + interval;
/* Count missed events. */
nanouptime(&uptime);
if (timespeccmp(&uptime, &tfd->tfd_time.it_value, >)) {
timespecsub(&uptime, &tfd->tfd_time.it_value, &uptime);
tfd->tfd_count += tstosbt(uptime) /
tstosbt(tfd->tfd_time.it_interval);
if (now > exp) {
diff = now - exp;
tfd->tfd_count += diff / interval;
next -= diff % interval;
}
timespecadd(&tfd->tfd_time.it_value,
&tfd->tfd_time.it_interval, &tfd->tfd_time.it_value);
callout_schedule_sbt(&tfd->tfd_callout,
tstosbt(tfd->tfd_time.it_value),
0, C_ABSOLUTE);
callout_schedule_sbt(&tfd->tfd_callout, next, 0, C_ABSOLUTE);
tfd->tfd_time.it_value = sbttots(next);
} else {
/* Single shot timer. */
callout_deactivate(&tfd->tfd_callout);